T-Mobile’s HTC Amaze 4G Compatible With AT&T 3G/4G?

Well, this was certainly out of left field. Apparently, some curious HTC Amaze 4G users over on XDA got to fiddling around with their devices and once they got to inserting an AT&T SIM card and setting the correct APN settings for AT&T… BOOM. Their HTC Amaze was connected to not only AT&T’s 3G, but their 4G data network as well.

Normally because of the incompatibility of T-Mobile’s bands 3G/4G bands with AT&T and “the rest of the world,” T-Mobile devices are never really a good choice for importing or unlocking for use on other carriers. Things were made even murkier with the inconsistent information provided by HTC on their website and the box of the Amaze. While I don’t recommend you run out and buy your own unlocked HTC Amaze for AT&T/Canada/UK, this could be good to know in case you ever run into a great deal on Craigslist.

Now that the HTC could be technically labeled as a “world phone,” has this made any of you guys consider importing or unlocking the device for your carrier? Hit up the source link to see the 4G results new HTC Amaze users have been experiencing on AT&T.

I wonder if AT&T’s assumption that the merger would go through, nearly a year ago, played a role in this?

http://pulse.yahoo.com/_TJXDF2RPGMXXMQXVTZTPSSLR3I Middle way

What is the big deal here? I have had unlocked Mytouch and MyTouch 4G phones from my T-mobile account and when I changed the SIM cards in Europe (Scandinavia, UK/Ireland, Germany) it worked perfectly for phone and data!! Am I missing something? May be it is just AT&T band – though I have never tried using AT&T SIM card in these phones. I do not think this has anything to do with the DOOMED merger.

http://ashn.myopenid.com/ Ash

ATT uses 850 and 1900, the rest of the world (mostly) uses 2100.

Usually both ATT and T-mo have their own bands + 2100, but not each other’s bands, that’s why it’s a big deal.

Who Knows

Chris,

I didn’t know the world was the US. When the 3G standard was introduced AT&T didn’t want to wait for the government to release the frequencies so they went with a non-standard frequency of 850/1900. Unfortunately all the major Canadian carriers followed this lead. The proper standard for 3G in North America is T-Mobile’s at 2100/1700, which Wind Moble, Mobilicity and Videotron use in Canada.

This is the reason why travellers from the rest of the world, you know Europe, Asia, etc, only get EDGE on AT&T and 3G on T-Mobile. It is also the reason why people go for T-Mobile phones to ship to Europe.

Research first. I believe what is happening is scale of economics. It is now cheaper to create one phone with all frequencies on it then 2 different versions. The HTC Amaze 4G from Telus is the exact same one that T-Mobile has, which means I can go anywhere in the world and get 3G.

zorxd

Most phones sold in Europe/Asia/Africa are NOT compatible with the 1700 MHz AWS band used by T-Mobile so they will fall back on EDGE too anyway.
Most phones are either dual band 900 and 2100 MHz, triple band 900, 1900 and 2100 MHz or quad-band 850, 900, 1900 and 2100 MHz. Only a few are triple band 900/1700/2100 MHz (such as the Nexus devices) or penta-band.

Who Knows

Europe/Asia/Africa run on UTMS Band I. They use the 2100MHz frequency for up and down traffic and 900MHz for voice, where as T-Mobile US uses Band IV (1700MHz Up and 2100MHz down), but they also support Band I. From experience, you can have a European phone and get 3G on T-Mobile, or the carriers that support 2100MHz in Canada. You will only get EDGE while on AT&T or the Big 3 in Canada.

This is the reason you can get 3G with a T-mobile US in the Europe, it’s the 2100MHz band that is the common link.

zorxd

If your European phone gets 3G on T-Mobile it’s because it happens to support the AWS (1700 MHz) band.
A 900/2100 MHz phone won’t work.

The 2100 MHz band isn’t a common link. The IMT and the AWS bands are two different bands even if they share the same frequencies for downlink.
You can have an IMT-only phone or an AWS-only phone.

John Holland

Actually Zorxd, you are wrong. The 2100 band is the exact link. I have an unlocked t-mobile MyTouch 4g, and I use it around the world while living in Belgrade.

The ATT versions of several great HTC phones do not work on 3g over here, precisely because they don’t have 2100.

And the author of this overall article is an idiot. T-Mobile is the only U.S. carrier compatible with the bulk of the world, not the other way around. It’s hard to believe an editor wouldn’t intervene when somebody writes something this stupid.

zorxd

No, I am right.
As I said, some phones are 900/1700/2100 MHz compatible which mean they will work both in Europe and on T-Mobile USA.
AT&T also have some 850/1900/2100 MHz phones which work in most of Europe.

However, a AWS-only phone wouldn’t work in Europe. And a 900/2100 MHz euro phone won’t work at all in the USA (it will have to fallback to GSM/EDGE mode)

http://pharaohtechblog.blogspot.com/ Conan Kudo (ニール・ゴンパ)

This is no surprise at all. FCC documents for the HTC Amaze 4G state that it supports WCDMA 850/AWS/1900, which means it supports HSPA+ on UMTS bands I/II/IV/V.

zorxd

AWS means only band IV, not I.

http://pharaohtechblog.blogspot.com/ Conan Kudo (ニール・ゴンパ)

While that is true, all UMTS AWS phones support UMTS band I as well, so it is generally implied. Additionally the FCC does not test for UMTS band I/III/VIII. Bands I and III are used to make up AWS, but so few European networks use UMTS band III that most phones don’t have it supported.

zorxd

AWS is a single band: 4
Band 1 is IMT (2100) and band 3 is DCS (1800)

The only thing is that the AWS band overlaps with the IMT and the DCS bands so they can’t be deployed at the same time in a given area.
So you can either deploy on:

AWS and PCS

or

IMT and DCS

but can’t mix both

And I beleive there are some cheap AWS-only phones which do not support the 2100 MHz band.
The LG Wink, for instance, is only compatible with bands 1700 and 850. Not 2100.

http://twitter.com/cayniarb cayniarb

This has to do with the Qualcomm chip used more than anything else. It’s their new this-chip-does-freaking-everything-but-lte-or-wimax solution. It should run on any 2G or 3G standard GSM system in the world (counting HSPA+ as 3G here). It is also the only chip capable of working with TMobUSA’s HSPA+42, and only used in 2 devices: the Amaze and the TMobUSA SGS2.